Smart building systems and methods

ABSTRACT

An appliance includes a memory storage location storing a flag indicative of a predicted demand-response (DR) period; and a controller coupled to the flag to autonomously place the appliance in an energy shedding mode during the predicted DR period. Additionally, a method is disclosed to fabricate a building structure includes depositing a phase change material (PCM) on a surface exposed to a conditioned air flow; and forming air channels on the PCM to increase thermal contact between the PCM and the conditioned air flow.

BACKGROUND

The present invention relates to smart building.

The ever increasing need for electricity has historically been satisfiedby building more power plants. However, the projected load growth andother external forces are pointing to projected peak capacity shortagein the near future.

One option to meet peak demand is called demand-response (DR). DR usestechnology and incentives to change electricity consumption by end-usecustomers. It can result in a reduction in energy consumption at timesof peak use and at times of high wholesale market prices. DR offersbenefits to both utilities and consumers in the form of increasedelectric system reliability and reduced price volatility. It uses a widerange of technologies offering a variety of options for both peaking andenergy capacities across the electrical system.

Energy demand at a premise varies over the time of day. In a typicalhome there is a peak in the morning when the family gets up, turns onlights, radios and televisions, cooks breakfast, and heats hot water tomake up for the amount used in showers. When the family leaves for workand school it may leave the clothes washer and dishwasher running, butwhen these are done, demand drops to a lower level but not to zero asthe air conditioners, refrigerators, hot waters and the like continue tooperate. Usage goes up as the family returns, peaking around dinner whenthe entire family is home. This creates the typical “double hump” demandcurve.

Businesses tend to follow different patterns depending on the nature ofthe business. Usage is low when the office is closed and relativelyconstant when the office is open. In extreme climates where airconditioning cannot be cut back overnight, energy use over the course ofthe day is more constant. Businesses such as restaurants may start laterin morning and their peaks extend farther into the evening. A factorywith an energy intensive process operating three shifts may show littleor variation over the course of the day.

SUMMARY

In one aspect, an appliance includes a memory storage location storing aflag indicative of a predicted demand-response (DR) period such as froma utility or when a current alternating current (AC) duty cycle differsfrom a specified AC duty cycle by a predetermined variance. Theappliance includes a controller coupled to the flag to autonomouslyplace the appliance in an energy shedding mode during the predicted DRperiod.

Implementation of the above system may include one or more of thefollowing. The predicted DR period occurs when the specified duty cyclecomprises 60 hertz and the current AC power duty cycle comprises about59.5 hertz or less. The appliance can include a wide area networkcoupled to the sensor; a server coupled to the wide area network,wherein for each appliance the server stores a location, a userpreference, and appliance properties, and wherein the server receivesperiodic operating state update and time stamp from each appliance. Thecontroller can determine the location of the appliance using an internetprotocol (IP) address. The controller indicates the location of theappliance using an address selected from one of a user entered address,an address stored in another appliance, and an address determined by apositioning system. The server determines a first group of appliances inan uninterruptible phase and sends a DR override instruction to thecontroller(s) in the first group. The server modulates operations ofappliances to avoid stressing the electrical grid. The appliance caninclude a sensor that compares the current AC duty cycle against thespecified AC duty cycle and sets the flag indicative of a predicteddemand-response (DR) period. An external power sensor can be placedexternal to the appliance, wherein the power sensor compares the currentAC duty cycle against the specified AC duty cycle and sets the flagindicative of a predicted demand-response (DR) period.

In one implementation, the appliance can be a refrigerator with an iceenergy storage chamber providing a predetermined cold energy for arefrigerated volume for the predicted DR period; and a fan to circulatecold air from the ice energy storage chamber inside the refrigeratedvolume during the predicted DR period. The refrigerator can include aphase change material coupled to the refrigerated volume to maintain therefrigerated volume at a predetermined temperature during the predictedDR period. The controller modulates compressor operation to reduce powerconsumption during the predicted DR period. The controller prechargesthe refrigerator prior to the predicted DR period. The controllerprecharges the refrigerator based on weather or warning from anauthority. The refrigerator can include ice storage to store coolth whenpower is available and used during the DR period. The fact that water isa pure substance and that making ice does not involve a chemicalreaction is one reason that ice storage is a relatively trouble freesystem.

In another implementation, the appliance is a water heater with aback-up heated energy storage chamber to store a reserve heated water tomaintained a predetermined temperature output for the water heaterduring the predicted DR period; and a valve to mix the reserve heatedwater with the water in the main water heater tank during the predictedDR period. The water heater can include a phase change material coupledto the water volume to maintain the water at a predetermined temperatureduring the predicted DR period. The water heater controller modulatesheater operation to reduce power consumption during the predicted DRperiod. The controller can precharge the water heater prior to thepredicted DR period or based on weather or warning from an authority.

In another implementation, the appliance can be a washer with adigitally actuated latch to secure a washer door during the predicted DRperiod. If the washer is in an uninterruptible cleaning operation duringthe predicted DR period, the controller reduces power consumption duringthe predicted DR period and subsequently repeats the uninterruptibleoperation after the predicted DR period. Further, if the washer is in anextendible cleaning operation during the predicted DR period, thecontroller reduces power consumption during the predicted DR period andsubsequently completes the extendible operation after the predicted DRperiod. The washer appliance can include a back-up heated energy storagechamber to store a reserve heated water to maintained a predeterminedtemperature output for the heater during the predicted DR period; and amixer to mix the reserve heated water with cold water to maintain apredetermined washing temperature during the predicted DR period. A datainput device can indicate the use of detergent additive or bleach usage,wherein the processor ignores the predicted DR period to avoid damage toitems in the washer.

In another aspect, systems and methods are disclosed to fabricate abuilding structure includes depositing a phase change material (PCM) ona surface exposed to a conditioned air flow; and forming air channels onthe PCM to increase thermal contact between the PCM and the conditionedair flow.

In another aspect, a method to fabricate a building structure mixing atexture aggregate filler mixed with a phase change material (PCM), saidfiller being selected from the group consisting of perlite, glassmicroballoons, glass bubbles, phenolic microballoons, and microspheres;and placing the PCM with the filler on a surface exposed to aconditioned air flow to increase thermal contact between the PCM and theconditioned air flow.

Implementations of the above aspect may include one or more of thefollowing. The building structure comprises a ceiling tile or anunderfloor air distribution (UFAD) panel. The process includes formingelongated hollow PCM structures. The elongated hollow PCM structures arefabricated in advance and attached to the building material duringfabrication or during shipping. The elongated hollow PCM structures areformed by dipping a scaffold into melted PCM. The process includesextruding the elongated hollow PCM structures with a predeterminedcross-sectional shape. The cross-sectional shape comprises one of:circular, hexagonal, rectangular, octahedron. The process includesforming a first layer of elongated hollow PCM structures and a secondlayer of elongated hollow PCM structures above the first layer. Theprocess includes forming air channels with grooves positioned on twoadjacent sides of the building materials to allow air flow through thePCM regardless of orientation of the building material. The processincludes spraying PCM onto the surface before forming air channels witha shaped tool. The process includes pouring PCM onto the surface beforeforming air channels with a shaped stamping tool. The process includesrolling PCM onto the surface before forming air channels with a shapedroller. The process includes dipping the surface into PCM and thenforming the air channels with a shaped tool. The process includesmicroencapsulating the PCM. The process includes characterizing PCMproperties and predicting building performance with the characterizedPCM properties. The process includes pre-charging a building by coolingthe PCM during a period of non-peak energy consumption and reducingenergy consumption during a peak period.

In another aspect, a method to fabricate a building structure includesmixing a phase change material (PCM) with a texture aggregate filler,said filler being selected from the group consisting of perlite, glassmicroballoons, glass bubbles, phenolic microballoons, and microspheres;spraying the aggregate filler PCM on a surface exposed to a conditionedair flow to increase thermal contact between the PCM and a conditionedair flow.

Implementations of the above aspect may include one or more of thefollowing. The process includes rolling the texture on the PCM with aroller. The process includes using a crow's foot stomp brush to form atexture to thermally interact with the air flow. The process includesstamping a texture on the PCM.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B show an exemplary smart grid home.

FIG. 2A and FIG. 2B show exemplary DR responsive appliances such as anexemplary water heater, an exemplary refrigerator, an exemplary dishwasher, an exemplary clothes washer, and an exemplary oven.

FIG. 3 shows an exemplary refrigerator.

FIG. 4 shows an exemplary water heater.

FIG. 5 shows an exemplary clothes washer.

FIG. 6 shows an exemplary dish washer.

FIGS. 7-11 show exemplary phase change material (PCM) ceiling tiles orfloor panels.

FIGS. 12A-12C show exemplary PCM fabrication equipment.

DESCRIPTION

FIG. 1A shows an exemplary smart grid home. The smart grid home includessmart building materials such as smart tile ceiling/floor panels andwindows/window shades, as discussed in depth below. In one embodiment,the home may include a roof refrigeration unit to store energy. Ice isone technical modality currently used in commercial buildingapplications to store “coolth” at night by running refrigerationequipment. During the day, the refrigeration equipment is turned off toreduce peak electrical demand. To store heat (from the sun, forexample), however, a different phase change material is needed.Alternatives to ice can be used. For example, paraffin, alone, andsolid-state phase change materials (PCM) can be incorporated intobuilding products such as wallboard and concrete. Microencapsulated PCMcan be used in window cover or fabrics to reduce temperaturefluctuations.

The windows allow sunlight or solar radiation into a building orstructure when the ambient temperature is low and substantially blocksolar radiation when the ambient temperature is high, especially whensunlight is directly on the window. This house provides windows thatallow passive solar heating and daylighting on colder days and stillprovide significant daylighting, while blocking solar heat build-up onwarmer days, especially from sunlight shining directly on or through thewindows of this invention. This house also provides thermochromicdevices such as variable transmission shutters for use as lenses orfilters.

Ultimately, it is the outdoor or ambient temperature and the directnessof the sun's rays that determine the need for energy blocking characterof windows. In a number of embodiments of this invention, the windows ofthis invention spontaneously change to provide energy blocking under theappropriate conditions of temperature and directness of sunlight withoutthe control mechanisms and user intervention required by most alternatetechnologies under consideration for use as dimmable windows. Otherembodiments of this invention provide windows that can be controlled byusers or be controlled automatically by, for example, electronic controlmechanisms, if so desired.

Windows have residual light energy absorbing character such that whenexposed to sunlight, (especially direct sunlight on warm or hot days),the temperature of at least a portion of the total window structure israised significantly above the ambient, outdoor temperature. The windowsand devices combine thermochromic character with this residual lightenergy absorbing character, juxtaposed in such a manner that there is anincrease in temperature of the materials responsible for thethermochromic character when there is an increase in temperature due tosunlight exposure of the materials responsible for the residual lightenergy absorbing character. The thermochromic character is such that thetotal light energy absorbed by the window increases as the temperatureof the materials responsible for the thermochromic character isincreased from the ambient, outdoor temperature to temperatures abovethe ambient, outdoor temperature.

The residual light energy absorbing character is provided by staticlight energy absorbing materials and/or thermochromic materials thathave some light energy absorbing character at ambient, outdoortemperatures. Preferably, any light energy absorbing character of thethermochromic materials at ambient outdoor, temperatures thatcontributes to the residual light energy absorbing character is due tothe more colored form of the thermochromic materials that exists becauseof the thermal equilibrium between the less colored and more coloredforms at outdoor, ambient temperatures or is due to the coloration ofthe less colored form and is not due to photochromic activity of thethermochromic materials. Preferably, the residual light energy absorbingcharacter is such that the window is capable of absorbing about 5% ormore and more preferably about 10% or more of the energy of solarirradiance incident on the window or device apart from any absorptionchanges caused by sunlight exposure. Preferably, the residual lightenergy absorbing character is such that there is a temperature increasein the materials responsible for the thermochromic character of at least10° C. and more preferably of at least 20° C. above the ambient, outdoortemperature when the window or device is exposed to direct or fullsunlight.

The thermochromic character can be provided by essentially any materialor materials which change reversibly from absorbing less light energy toabsorbing more light energy as the temperature of the material ormaterials is increased. It is preferred that the thermochromic characterbe provided by materials that have a smaller absorption at outdoor,ambient temperatures on warm and hot days and have an increase inabsorption when the temperature of the materials responsible for thethermochromic character is increased at least 10° C. It is preferredthat the thermochromic character be provided by materials that have evenless absorption at outdoor, ambient temperatures on cool and cold daysand a less significant increase in absorption when the temperature ofthe window increases due to exposure to direct or full sunlight on cooland cold days.

The windows optionally combine other characteristics like lowemissivity, infrared light reflectance, barrier properties, protectiveovercoating, multipane construction and/or special gas fills to provideenergy efficient windows.

Energy efficient windows and devices of the invention can have one ormore thermochromic layers which change from absorbing less light energyto absorbing more light energy as the temperature of the thermochromiclayer(s) is increased. For many of the thermochromic layers used in theinvention, this means a change from less colored to more colored as thetemperature of the thermochromic layer(s) is increased.

Windows and devices of the invention can have one or more substrates,(i.e. window pane, panel, light or sheet). The substrate may be athermochromic layer or the substrate may have thermochromic layer(s)provided thereon. Windows of the invention may comprise two or moresubstrates spaced apart by spaces containing gas or vacuum.

Windows optionally include a barrier to short wavelength light. Theshort wavelength light may be ultraviolet (UV) light. The shortwavelength light may, optionally, include short wavelength visible (SWV)light. The barrier may absorb some or all of the UV and/or SWV lightincident on the barrier layer. The barrier may be a substrate, a portionof a substrate, (e.g., the barrier may be in a polymeric layer adheringtwo sheets of glass together), or the barrier may be a layer provided ona substrate. The barrier, if present, is located between the sun and thethermochromic layer and serves to protect and/or modify the behavior ofthe thermochromic layer and possibly other layers present. The barriercan protect other layers, for example, from photodegradation by UV lightand can modify the behavior of the thermochromic layer by suppressingsome or all of the photochromic character of materials present whichhave both thermochromic and photochromic character. In many cases, thethermochromic materials will be incorporated into a polymeric materialwhich includes an additive such as a UV stabilizer. While thisstabilizer does not ordinarily provide the equivalent effect of abarrier layer, devices have been constructed without a barrier layerwhen a UV stabilizer is present in the thermochromic layer.

Windows may have a protective overcoat. This overcoat, if present,serves to protect the thermochromic layer and optionally any other layerwhich may be present from, for example, physical abrasion, oxygen andenvironmental contaminants. The thermochromic layer is located betweenthe sun and the protective overcoat, if it is present, e.g., a windowpane of glass/thermochromic layer/protective overcoat may be orientedwith the overcoat on the inside surface of the window structure.

Windows may also have one or more static light energy absorbingmaterials. These materials provide relatively constant light energyabsorption, (i.e. absorption which is not significantly dependent on thetemperature or photochemical processes of the light energy absorbingmaterial). The static light energy absorbing material(s), if present,serves to provide residual light energy absorbing character and thusabsorbs enough light energy during direct or full sunlight exposure toraise the temperature of at least a portion of the window above theambient temperature surrounding the window. This helps to make thewindows responsive to the directness of the sunlight. The static lightenergy absorbing materials may be contained in a separate layer, in thesubstrate, and/or any of the other layers present including thethermochromic layer as long as the absorbed energy is able to warm thethemochromic material to a temperature at which the thermochromicmaterial increases in sunlight absorption.

Windows may have one or more low emissivity, (low-e), layers. The low-elayer(s) helps provide energy efficiency by its ability to reflectinfrared, (IR), light and/or its ability to poorly emit or radiate IRlight.

Using the thermochromic layers, the roof can turn white during summerdays to reflect sunlight and minimize heat inside the house and can turnblack during winter months to absorb heat to warm the house.

The carpet can also have a multi-component PCM fibre, wherein a firstfibre body consists of a first material comprising a phase changematerial and a second fibre body consists of a second material andencloses the first fibre body, wherein the phase change material is inraw form and the first material comprises a viscosity modifier selectedfrom polyolefines having a density in the range of 890-970 kg/m 3 asmeasured at room temperature according to ISO 1183-2 and a melt flowrate in the range 0.1-60 g/10 minutes measured at 190° C. with 21.6 kgweight according to ISO 1133.

The expression “raw form” is intended to mean that the PCM is introducedin its raw form at the manufacturing of the multi-component fibre, i.e.that the PCM is not encapsulated, the PCM is neither carried on or byanother material solid at the spinneret temperature during spinning ofthe multi-component fibre, such as soaked into a porous structure,wherein the structure is solid at the spinneret temperature duringspinning of the multi-component fibre. Thus, the PCM is considered as in“raw form” in spite of it being mixed with the viscosity modifier atmanufacturing the multi-component fibre.

Polymers having a melt flow rate in the range 0.1 to 60 g/10 minutesmeasured at 190° C. with 21.6 kg weight are suitable as viscositymodifiers in the multi-component fibre. Many of the efficient PCMmaterials are low molecular compounds and such compounds possess lowviscosities at the relevant processing temperatures (180-300° C.). Inorder to make multi-component fibres with a sheath material, the secondmaterial, having a higher viscosity at the processing temperature, theinventors have now found that if the phase change material is mixed witha polyolefin having a melt flow rate in the range 0.1-60 g/10 minutes, afibre having high latent heat and which is strong is obtained. Thepolyolefin is a viscosity modifier, which increases the viscosity of thefirst material of the multi-component fibre.

A low amount of a viscosity modifier having a melt flow rate in therange 0.1-60 g/10 minutes may be used, which is an advantage for thethermal efficiency in terms of specific latent heat and at the same timeallow the full utilisation of the inherent specific latent heat ofmelting/crystallisation of the phase change material. If a higher valuethan 60 g/10 minutes is used, the viscosity will be too low and themixture will not be possible to process a fibre. The mixture will be“watery”, i.e. very thin. A value lower than 0.1 g/10 minutes of theviscosity modifier might lead to curling of the fibres and fibrespinning may not be possible.

As shown in FIG. 1B, apparatus 101 includes a unit 103 comprising acontroller 104 and an internal storage device 105. Internal storagedevice 105 may comprise, for example, a plurality of lead-acid ornickel-metal-hydride storage batteries for storing electrical energy,and/or large capacitors. External storage device 106 may be optionallyincluded to store additional electrical energy. As explained in moredetail herein, storage devices 105 and 106 may provide power to variousdevices during times of electrical grid outages or during periods whereelectrical grid costs exceed certain thresholds, and they may be used tosell power back to the electrical utility during times that aredetermined to be favorable. The storage capacities of devices 105 and106 may be selected to suit a particular environment, such as the needsof a typical home residence, business, or other electrical consumer.

Storage in the form of compressed air is usually discounted due to thepoor thermodynamic efficiency, but the capital cost is low and in somecases the marginal value of solar power is zero (when supply exceedsdemand the excess cannot be sold or stored by other means), socompressed air storage may be practical in some embodiments of theinvention. Finally, in some specific locations it may be possible tostore power by pumping water to an elevated water tower or reservoir(pumped storage) which could increase storage capacity by another factorof 10. Power electronics, including inverters for converting DCelectrical energy into AC energy, circuit breakers, phase converters andthe like, may also be included but are not separately shown in FIG. 1.

Controller 104 may comprise a computer and memory programmed withcomputer software for controlling the operation of apparatus 101 inorder to receive electrical power from power sources 109 through 115 andto distribute electrical power to devices 116 through 122. Furtherdetails of various steps that may be carried out by such software aredescribed in more detail herein.

As the building may contain non-electrical energy storage materialsembedded in a building, the controller precharges the materials embeddedin at least a ceiling, a floor, window, wallboard, or concrete of abuilding in advance of an expected DR period. In one embodiment, thecontroller creates in advance computer models of the non-electricalenergy storage materials or sources and uses the models to precharge thenon-electrical energy storage material or the non-electrical energysource in advance of an expected DR period. The computer model can bestatistical or non-statistical. For example, Hidden Markov Models (HMMs)can be used to model building energy behavior and such models can beused to precharge the building thermal envelopes.

The ability to pre-charge the building supports utility DR programs,since off-peak power such as night time can be used to store energy inthe non-electrical energy storage materials and non-electrical energystorage sources of energy and such energy can be used to supplement thereduced power during the DR period.

Controller 104 and internal storage device 105 may be housed in a unit103 such as a metal rack having appropriate cabling and supportstructures. Apparatus 101 also includes a user interface 102 forcontrolling the operation of unit 103. The user interface may comprise akeypad and CRT, LED or LCD display panel or vacuum fluorescent type; acomputer display and keyboard; or any other similar interface. The userinterface may be used to select various modes of operation; to displayinformation regarding the operation of the apparatus; and forprogramming the apparatus.

An optional control center 108 may be provided to transmit commands toapparatus 101 through a network, such as WAN 107 (e.g., the Internet).Control center 108 may be located at a remote location, such as acentral control facility, that transmits commands to a plurality ofunits 101 located in different homes or businesses. In addition totransmitting commands, control center 108 may transmit pricinginformation (e.g., current price of electricity) so that controller 104may make decisions regarding the control and distribution of electricityaccording to various principles of the invention.

Apparatus 101 is coupled to the electric utility grid 115 through apower interface (not shown), which may include circuit breakers, surgesuppressors and other electrical devices. Electricity may be supplied invarious forms, such as 110 volts or 240 volts commonly found in homes. Abackup generator 114 may also be provided and be controlled by apparatus101 when needed. One or more alternative energy sources 109 through 113may also be provided in order to provide electrical power to theapparatus. Such sources may include photovoltaic (PV) cells 109, whichmay be mounted on a roof of the home or business; micro-hydroelectricpower generators 110, which generate power based on the movement ofwater; gas turbines 111; windmills or other wind-based devices 112; andfuel cells 113. Other sources may of course be provided.

During normal operation, power from one or more of the power sources canbe used to charge storage units 105 and 106 and/or to meet demand inaddition to electric grid 115. During power outages or brownouts fromgrid 115, these additional power sources (as well as storage units 105and 106) can be used to meet energy demand. Additionally, surplus powercan be sold back to the power grid based on optimization of supply anddemand calculations as explained in more detail herein.

The bold lines shown in FIG. 1 indicate electrical distribution paths.Control paths to and from the various devices are not separately shownbut are implied in FIG. 1.

One or more power-consuming devices 116 through 122 may also becontrolled by and receive power from apparatus 101. These include one ormore sensors 116 (e.g., thermostats, occupancy sensors, humidity gaugesand the like); heating/ventilation/air-conditioning units 117; hot waterheaters 118; window shades 119; windows 120 (e.g., open/close and/ortint controls); and one or more appliances 121 (e.g., washing machines;dryers; dishwashers; refrigerators; etc.). Some appliances may beso-called “smart” appliances that can receive control signals directlyfrom apparatus 101. Other conventional appliances can be controlledusing one or more controllable relays 122. It is not necessary in allembodiments that apparatus 101 directly provide electricity to devices116 through 112. For example, apparatus 101 could be tied into theelectrical power system in a home or business and electricity would besupplied through that path to the devices. Appropriate cut-off devicesand bypass switches would then be used, for example, in the event of apower outage to disconnect the home wiring system from the electricalgrid and to connect apparatus 101 to the wiring network. Such schemesare conventional and no further details are necessary to understandtheir operation.

The next several figures show exemplary DR responsive appliancesincluding an exemplary water heater, an exemplary refrigerator, anexemplary dish washer, an exemplary clothes washer, and an exemplaryoven.

FIG. 2A shows an exemplary appliance 6 with a processor 4 and embeddedmemory storage location storing a flag indicative of a predicteddemand-response (DR) period when a current alternating current (AC) dutycycle differs from a specified AC duty cycle by a predeterminedvariance. This is detected by AC duty cycle detector 2. The processor orcontroller 4 is connected to the detector or sensor 2 to autonomouslyplace the appliance in an energy shedding mode during the predicted DRperiod without receiving an explicit load shedding command from autility or a power generator.

In one embodiment, the predicted DR period occurs when the specifiedduty cycle comprises 60 hertz and the current AC power duty cyclecomprises about 59.5 hertz or less. The appliance can include a widearea network coupled to the sensor; a server coupled to the wide areanetwork, wherein for each appliance the server stores a location, a userpreference, and appliance properties, and wherein the server receivesperiodic operating state update and time stamp from each appliance. Thecontroller can determine the location of the appliance using an internetprotocol (IP) address. The controller indicates the location of theappliance using an address selected from one of a user entered address,an address stored in another appliance, and an address determined by apositioning system. The server determines a first group of appliances inan uninterruptible phase and sends a DR override instruction to thecontroller(s) in the first group. The server modulates operations ofappliances to avoid stressing the electrical grid. The appliance caninclude a sensor that compares the current AC duty cycle against thespecified AC duty cycle and sets the flag indicative of a predicteddemand-response (DR) period. An external power sensor can be placedexternal to the appliance, wherein the power sensor compares the currentAC duty cycle against the specified AC duty cycle and sets the flagindicative of a predicted demand-response (DR) period.

Preferably, the control system of each appliance is done with digitalsignal controllers with smaller, quieter motors with energy efficiencyas high as 85%-90%. A high efficiency is necessary to receive a stamp ofapproval from a governing body such as the US Environmental ProtectionAgency and Department of Energy ENERGY STAR rating. The appliances alsocomply with IEC 60730 specification covering mechanical, electrical,electronic, EMC, and abnormal operation of AC appliances. Formicrocontrollers, the specification details new test and diagnosticmethods for the real-time embedded software to ensure the safe operationof embedded control hardware and software. For larger,higher-performance products where reliability and motor-control accuracyare key concerns, isolation products block high voltage, isolategrounds, and prevent noise currents from entering the local ground andinterfering with or damaging sensitive circuitry. The digital signalcontrollers perform digital motor control, Power Factor Correction, andother system functions. A home mesh network consisting of homeappliances, audio/video equipment, HVAC system, lighting fixtures, etcconnected wirelessly and controlled via a remote control over ZigBee™network. Thus, appliances can communicate with each other by creatingintelligent home networks such that, for example, a wash load iscompleted and a message be displayed on your TV, or LCD display on yourrefrigerator or remote control. With low-power wireless solutions, homeowners will benefit from a universal remote control that: does notrequire line-of-sight; has an increased range such that one can remotelycontrol any ZigBee device from anywhere in the home; allows for two-waycommunication.

In one embodiment, refrigerator is equipped with RFID and allowscustomers to keep an up-to-date inventory of their refrigerated goodsand have this information displayed on a video display that may resideon the refrigerator door. Once RFID tags on individual household goodsbecome commonplace in the market, RFID-equipped refrigerators will beable to automatically identify the item as it is being taken in and outof the unit. This will happen once the large chain food retailersthemselves use RFID as their main mechanism for receiving payment at thecheckout counter.

Referring to FIG. 2B, additional details regarding power managementdevice 16 and appliance 18 according to one possible embodiment arepresented. The power management device 16 and associated appliance 18may be referred to as an electrical energy consumption system.

The depicted power management device 16 includes an interface 20 andcontrol circuitry 24. Interface 20 is arranged to receive operationalelectrical energy for consumption using the respective appliance 18.Interface 20 may be referred to as a power interface and comprise thenode described above. Interface 20 may be implemented using a walloutlet adapter able to receive supplied residential, commercial,industrial, or other electrical energy in exemplary configurations.Control circuitry 24 may be embodied as a microprocessor or otherappropriate control architecture.

The depicted exemplary appliance 18 comprises control circuitry 30, aplurality of associated loads 50, and a plurality of relays 52. Controlcircuitry 30 may be implemented as a microprocessor or other appropriatecontrol architecture and may also comprise an associated load 50.Associated loads 50 consume electrical energy. Relays 52 selectivelysupply electrical energy power from grid 14 to respective loads 50. Inother configurations, a single relay 52 may supply electrical energy toa plurality of loads 50 of a given appliance 18. Other configurationsfor controlling the application of electrical energy from interface 20to load(s) 50 are possible.

Power management device 16 may be configured according to the exemplarydevice arrangements described in the incorporated patent application.Power management device 16 is arranged in one embodiment as a discretedevice separate from the appliance 18 as mentioned above. Alternately,power management device 16 may be implemented entirely or partiallyusing existing components of the appliance 18. For example,functionality of control circuitry 24 may be implemented using controlcircuitry 30 to monitor electrical energy of power distribution system10 and to control consumption of electrical energy by one or more ofloads 50 responsive to the monitoring. As described in the incorporatedpatent application, a relay (or other switching device not shown in FIG.2) internal of device 16 may be used to adjust the amount of electricalenergy consumed by appliance 18. Control circuitry 24 and/or controlcircuitry 30 may be arranged to control the operations of the associatedrelay (not shown) of device 16. As shown, appliance 18 may compriseassociated relays 52 which may be controlled by control circuitry 24and/or control circuitry 30. Switching device configurations other thanthe described relays may be used.

In other arrangements, control circuitry 24 may provide control signalsto control circuitry 30 or directly to loads 50 to control the rate ofconsumption of electrical energy by loads 50 without the use of relays52 (accordingly relays 52 may be omitted). Responsive to the receivedcontrol signals, control circuitry 30 may operate to control respectiveloads 50, or loads 50 may internally adjust rates of consumption of theelectrical energy responsive to directly receiving the control signalsfrom circuitry 24 or 30.

According to the specific arrangement of the appliance 18 beingcontrolled, aspects described herein, including monitoring of electricalenergy of system 10 and/or controlling the consumption of power withinappliance 18, may be implemented using circuitry internal and/orexternal of the appliance 18. The discussion herein proceeds withrespect to exemplary configurations wherein monitoring and controloperations are implemented by control circuitry 30. Any alternateconfigurations may be used to implement functions and operationsdescribed herein.

Appliances 18 comprise devices configured to consume electrical energy.Exemplary appliances 18 described below include temperature maintenancesystems, HVAC systems, clothes dryers, clothes washers, water managementsystems (e.g., spa and/or pool), dish washers, personal computersystems, water heaters, and refrigerators. The described appliances 18are exemplary for discussion purposes and other arrangements arepossible.

As shown in the exemplary arrangement of FIG. 2, appliances 18 mayindividually comprise a plurality of different associated loads 50individually configured to consume electrical energy. For example, for agiven appliance 18, one of loads 50 may be a control load whereinprocessing is implemented (e.g., 3-5 Volt circuitry of control circuitry30) and another of the loads 50 may be a higher voltage load includingexemplary motors, heating coils, etc. The controller of FIG. 2B cancharge an energy reservoir 26 to provide energy during the DR period.The reservoir 26 can be ice energy for powering a refrigerator, or hotwater to back up a washer or water heater, for example.

Consumption of electrical energy by such appliances 18 may be adjustedby turning off (or otherwise adjusting the operation of one associatedload 50 while leaving another associated load 50 powered (or otherwiseunaffected). During exemplary power management operations, it may bedesired adjust an amount of electrical energy applied to one of theassociated loads 50 of a given appliance 18 (e.g., a high powerassociated load) while continuing to provide full (or otherwiseunadjusted) amount of electrical energy to another of the associatedloads 50 of the given appliance 18 (e.g., a low power associated load).Alternately, power may be adjusted, reduced or ceased for all associatedloads all together.

Adjustment of the consumption of electrical energy by an appliance 18may be implemented responsive to monitoring by appropriate controlcircuitry of electrical energy of power distribution system 10. In oneembodiment, a characteristic (e.g., system frequency) of the electricalenergy is monitored. The incorporated patent application providesexemplary monitoring operations of system frequency (e.g., voltage) ofelectrical energy supplied by power distribution system 10. Othercharacteristics of electrical energy of system 10 may be monitored inother constructions.

Responsive to the monitoring, appropriate control circuitry isconfigured to adjust an amount of consumption of electrical energywithin at least one of the loads 50 from an initial level of consumptionto another different level of consumption. For example, as described inthe incorporated application, if the system frequency of the electricalenergy deviates a sufficient degree from a nominal frequency, athreshold is triggered. As described in the incorporated application,the threshold may be varied at different moments in time (e.g.,responsive to power-up operations of appliance 18 at different momentsin time). In one embodiment, the varying of the threshold is random.

Appropriate control circuitry may adjust an amount of consumption ofelectrical energy (e.g., via one of loads 50) from an initial level toanother different level (e.g., reduced consumption mode) responsive tothe threshold being triggered. Thereafter, the control circuitrycontinues to monitor the electrical energy. If the frequency returns toa desired range, the control circuitry may return the operation of theappliance 18 and load(s) 50 to a normal mode of operation (e.g., a modewherein an increased amount of electrical energy is consumed). Asdescribed in the incorporated patent application, a variable length oftime may be used to return the consumption to the initial level and thevariable length of time may be randomly generated in at least oneembodiment.

Accordingly, the appropriate control circuitry may control operation ofthe adjusted load 50 for a period of time at the adjusted level ofelectrical energy consumption. During the adjustment, the controlcircuitry may maintain the level of consumption of another load 50 ofthe appliance 18 at a normal level of consumption.

Some arrangements of power management device 16 permit overridefunctionality. For example, the appropriate control circuitry may haveassociated user interface circuitry (not shown) usable by a user todisable power management operations via an override indication (e.g.,hit a key of the user interface circuitry). Responsive to the receptionof the override indication, the control circuitry may return the mode ofoperation of the affected load 50 to a normal consumption mode (e.g.,wherein an increased amount of electrical energy is consumed comparedwith the level of consumption initiated during the power managementoperations).

FIG. 3 shows an exemplary refrigerator. The illustrated refrigerator 140includes control circuitry 30 i (embodying a thermostat 142), a heatingelement 144, a fan 146, a compressor 148, and a solenoid valve 150 inthe depicted embodiment. Control circuitry 30 i, heater 144, fan 146,and compressor 148 comprise exemplary loads 50 i in the depictedexample. The refrigerator 140 also include an ice energy storage chamber152. The embodiment uses ice storage to store coolth and used when theDR period is active.

First exemplary power management operations of control circuitry 30 iinclude adjustment of a temperature set point of thermostat 142. It maybe desired in at least one embodiment to set a relatively short durationof any temperature adjustment during power arrangement operations.Another possible power management operation provides temporarydisablement of defrost operations of heating element 144 (e.g., coupledwith unillustrated coils of refrigerator 140), or adjusting a time ofthe defrost operations controlled by control circuitry 30 i. In anotherarrangement, heating element 144 may be used to provide anti-sweatoperations (e.g., appropriately positioned adjacent an exterior portionof an unillustrated cabinet of refrigerator 140—for example adjacent toa door) and power management operations may include temporarydisablement of the anti-sweat operations or otherwise adjusting suchoperations to occur at another moment in time wherein power managementoperations are not being implemented. Additional exemplary powermanagement operations include disablement of interior air circulationoperations implemented by fan 146 and/or controlling operations ofcompressor 148 (e.g., including temporarily disabling or reducing thespeed of compressor 148). Additional aspects include implementing a hotgas bypass operation of compressor 148 using solenoid valve 150 and asdescribed in further detail above in one example. One other embodimentprovides a multi-stage refrigerator 140 having a plurality of coolingstages and a power management operation includes controlling therefrigerator 140 to operate at less than the available number of coolingstages thereby reducing the amount of energy consumed by the appliance.

In one implementation, the refrigerator ice energy storage chamberprovides a predetermined cold energy for a refrigerated volume for thepredicted DR period; and a fan to circulate cold air from the ice energystorage chamber inside the refrigerated volume during the predicted DRperiod. The refrigerator can include a phase change material coupled tothe refrigerated volume to maintain the refrigerated volume at apredetermined temperature during the predicted DR period. The controllermodulates compressor operation to reduce power consumption during thepredicted DR period. The controller precharges the refrigerator prior tothe predicted DR period. The controller precharges the refrigeratorbased on weather or warning from an authority. The refrigerator caninclude ice storage to store coolth when power is available and usedduring the DR period. The fact that water is a pure substance and thatmaking ice does not involve a chemical reaction is one reason that icestorage is a relatively trouble free system.

FIG. 4 shows an exemplary water heater. Water heater 150 includescontrol circuitry 30 h (embodying a thermostat 152 in the illustratedconfiguration) and a heating element 154. Heating element 154 isconfigured to heat water in a main reservoir 156 and an associatedreservoir 158 to a desired temperature in the depicted configuration.Control circuitry 30 h and heating element 154 comprise loads 50 h ofwater heater 150 in one embodiment.

According to an illustrative embodiment, power management operations ofsystem 150 and implemented by control circuitry 30 h include adjusting aset point of thermostat 152. For example, the thermostat set point maybe temporarily lowered (e.g., for a period of tens of seconds, or a fewminutes in some examples). In other exemplary power managementoperations, control circuitry 30 h may directly disable or provide othercontrol of heating element 154 and gate pre-heated water from the backup reservoir 158 during the DR period.

According to additional exemplary aspects, a set point of any of thethermostats disclosed herein of the various appliances may be assignedto one of a plurality of possible power management set points accordingto a monitored condition of electrical energy of system 101. Forexample, a scale of set points may be used according to the condition ofthe electrical energy (e.g., the temperature set point may be decreasedat predefined decrements (1-10 degrees for example) corresponding to thesystem frequency of the electrical energy deviating respectivepredetermined amounts (e.g., 10 mHz) from the nominal frequency. Inaccordance with the described example, the magnitude of adjustment ofthe thermostat set point increases as the deviation of the systemfrequency from the nominal frequency increases.

In one implementation, the water heater 150 uses the back-up heatedenergy storage chamber 158 to store a reserve heated water to maintaineda predetermined temperature output for the water heater during thepredicted DR period; and a valve to mix the reserve heated water withthe water in the main water heater tank during the predicted DR period.The water heater can include a phase change material coupled to thewater volume to maintain the water at a predetermined temperature duringthe predicted DR period. The water heater controller modulates heateroperation to reduce power consumption during the predicted DR period.The controller can precharge the water heater prior to the predicted DRperiod or based on weather or warning from an authority.

FIG. 5 shows an exemplary clothes washer. In one implementation, thewasher has a digitally actuated latch to secure a washer door during thepredicted DR period. If the washer is in an uninterruptible cleaningoperation during the predicted DR period, the controller reduces powerconsumption during the predicted DR period and subsequently repeats theuninterruptible operation after the predicted DR period. Further, if thewasher is in an extendible cleaning operation during the predicted DRperiod, the controller reduces power consumption during the predicted DRperiod and subsequently completes the extendible operation after thepredicted DR period. The washer appliance can include a back-up heatedenergy storage chamber to store a reserve heated water to maintained apredetermined temperature output for the heater during the predicted DRperiod; and a mixer to mix the reserve heated water with cold water tomaintain a predetermined washing temperature during the predicted DRperiod. A data input device can indicate the use of detergent additiveor bleach usage, wherein the processor ignores the predicted DR periodto avoid damage to items in the washer.

Referring to FIG. 5, the exemplary clothes washer 160 may includecontrol circuitry 30 d, a heating element 162, and an agitator motor164. Heating element 162 is configured to heat water used in anassociated compartment (not shown) of clothes washer 160 configured toreceive and wash clothes. Heating element 162 is also used to heat awater reservoir 168 for use during the temporary DR period so thatwashing operations can continue. Agitator motor 164 is configured tooscillate between different rotational directions or otherwise agitateclothes within the associated compartment during wash and/or rinseoperations. Control circuitry 30 g, heating element 162 and agitatormotor 164 comprise associated loads 50 g of clothes washer 160 in thedepicted embodiment.

In one configuration, power management operations of clothes washer 160include reducing or ceasing the supply of electrical energy to heatingelement 162 to reduce internal temperatures of water in the associatedcompartment and/or agitator motor 164 to reduce motion of the motor 164.The reduction in power by controlling heating element 162 may be linearand accordingly the benefits may be directly proportional to thereduction in the water temperature. The reduction in power to agitatormotor 164 may be proportional to a product of angular acceleration, massand angular velocity. A slowing down of agitator motion of motor 164could affect both a reduction in acceleration as the motor reverses itsmotion as well as angular velocity. In other embodiments, it may bedesired to maintain agitator motor 164 in an operative mode during animplementation of power management operations with respect to heatingelement 162.

An exemplary clothes dryer may similarly include control circuitry, aheating element, and a tumbler motor. Heating element is configured inone embodiment to heat an associated compartment (not shown) of clothesdryer configured to receive and dry clothes. Tumbler motor is configuredto spin clothes within the associated compartment during dryingoperations. In one configuration, power management operations of clothesdryer include reducing or ceasing the supply of electrical energy toheating element (e.g., reducing an amount of current supplied to heatingelement) and/or tumbler motor. It may be desired to maintain tumblermotor in an operative mode during an implementation of power managementoperations with respect to heating element.

FIG. 6 shows an exemplary dish washer. Dish washer 170 includes controlcircuitry 30 f, a water heating element 172, a forced air heatingelement 174, and a water pump 176 in but one embodiment. Dish washer 170may additionally include a compartment (not shown) configured to receiveto dishes. Water heating element 172 may adjust a temperature of waterused to wash dishes using dish washer 170 in one embodiment. Heatingelement 172 is also used to heat a reservoir 178 to provide hot washingwater during a DR period. Forced air heating element 174 adjusts atemperature of air used to dry the dishes in one implementation. Waterpump 176 may spray water on the dishes during a cleaning and/or rinsingcycle to provide a dish cleaning action and/or rinsing action. Controlcircuitry 30 f, heating elements 172, 174, and water pump 176 maycomprise associated loads 50 f of dish washer 170.

Exemplary power management operations of dish washer 170 implemented bycontrol circuitry 30 f in one embodiment include controlling the waterheater 172 to reduce a water temperature boost cycle during washoperations and/or reduce air temperature by forced air heater 174 duringrinsing/drying operations. Reduction of water temperature providescorresponding linear reductions in electrical power consumption. Controlcircuitry 30 f may also control operations of water pump 176 (e.g.,reduce the operational speed of pump 176) during modes of reduced powerconsumption.

Turning now to FIG. 7, an exemplary ceiling tile 200 is shown with phasechange materials on one or more air ventilation structures 202. Thephase change material (PCM) contributes to the energy efficiency ofbuildings by reducing the peaks in the daily temperature cycles. As partof normal overnight ventilation, the warm air in the building isreplaced by cold night-time air, which also reduces the temperature ofthe building's solid structures over the course of the night. PCM canincrease the heat capacity of the building, meaning that additional‘coldness’ can be stored in the building's structures. With our system,it may be possible that mechanical air conditioning is not needed atall; as a minimum, the energy consumption for air conditioning can bereduced. The structure 202 is hollow at the center to maximize air flowand thermal conductance between the PCM material and the air. The PCMstructure has a plurality of microencapsulated PCM balls or capsuleswith wax or paraffin 208 inside of a polymer coating 208.

The phase change materials include alkanes, paraffin waxes and salthydrates. These materials undergo a reversible solid to liquid phasechange at various transition temperatures. ‘Solid-state’ phase changematerials are those that change from amorphous to crystalline phaseswhile remaining ‘solid.’ Both paraffin wax and salt hydrates typicallyrequire encapsulation to contain the liquid phase, which adds to finalcost of this PCM. Salt hydrates are inorganic materials. Inorganiccompounds have twice the volumetric latent energy storage compared toorganic compounds. The organic compounds however, have the advantages ofmelting congruently and are non-corrosive. Salt hydrates will meltincongruently causing phase separation. There are two categories ofsolid-state phase change materials: layered perovskites and plasticcrystals. The transition temperature of solid-state phase changematerials in a pure form runs on the higher side for use in passiveapplications. By mixing these compounds in various ratios, thetransition temperature can be lowered.

PCM can use paraffin waxes which are part of a family of saturatedhydrocarbons. The structure is the type C_(n)H_(2n+2). Those with carbonatoms between five and fifteen are liquids at room temperatures and arenot considered. Normal or straight chain and symmetrically branchedchain paraffin waxes are the most stable. Typically, paraffin waxes withodd numbers of carbon atoms are more widely used because they are moreavailable, more economical and have higher heats of fusion. Paraffinwaxes are composed mainly of alkanes, approximately 75%. Alkanes andparaffin waxes are both organic compounds. Paraffin can contain severalalkanes resulting in a melting range rather than a melting point. As themolecular weight increases, the melting point tends to increase as well.Using different mixtures of alkanes, specific transition temperaturesfor paraffin waxes can be attained. Paraffin waxes and alkanes at thetransition temperature melt to a liquid and solidify upon cooling. Theydo not have the containment problems of salt hydrates. The properties ofnormal paraffin wax are very suitable for latent heat storage. They havea large heat of fusion per unit weight, they are non-corrosive,nontoxic, chemically inert and stable below 500° C. (932° F.). Onmelting, they have a low volume change and a low vapor pressure. Mixingdifferent molecular weight paraffin waxes together can easily varymelting temperature. Since they are commercially available, the cost isreasonable. Prime candidates for passive applications are tetradecane,hexadecane, octadecane and eicosane. Paraffin wax has a low thermalconductivity. However, the addition of additives such as graphite couldincrease the thermal conductivity. A Boulder, Colo. company, OutlastTechnology, distributes outerwear made of fabrics that incorporateencapsulated paraffin wax. The Outlast Technology fabric involves themicroencapsulation of microscopic size droplets of paraffin wax. Theseencapsulated particles of wax are then incorporated into fabrics andfoams that are used for lining materials.

Pure octadecane is very close to the defined ideal passive temperature.By mixing normal alkanes of different molecule weights, the melting ortransition temperature can be altered from that of the pure form. Thelatent heat of a blend can be found from a linear equation, presentedas:

Final Blend J/g=(wt. %_(mPCM1)×J/g_(mPCM1))+(Wt. %_(mPCM2)×J/g_(mPCM2))+. . .

Octadecane in its pure form has a relatively high heat of fusion with atransition temperature close to an ideal passive temperature. Its latentheat storage is more than three times greater than the NPG/PG mixture.Based on thermal storage capabilities, octadecane is the superiormaterial, followed by the Kenwax 18.

Paraffin wax and solid-state phase change materials show the behavior ofunder or super cooling. This behavior occurs when the material does notsolidify at the same temperature at which it melted. Solid-state phasechange materials have shown more than a twenty-degree difference. Thedifference is not as noticeable in paraffin waxes. Other phase changematerials can be used.

The PCM structure can be glued or secured to the tile. Preferably, thecomposite structure is less than 20% by mass of a binder material andthe remaining mass is a phase change material (PCM).

The PCM ceiling tile concept is based on reducing peak air-conditioningloads in a space. To do this, the space is overcooled slightly duringoff peak hour, say to 68 F. Air returning through the ceiling plenumcools and solidifies the phase change material on the top of the ceilingtile. During the day the room thermostat is set to a higher temperature,say 75 F. The air passing through the plenum, entering the plenum at 75F, is warmed further by light fixture ballasts in the ceiling. Withoutthe PCM ceiling tile the air would return to the air handler at about 80F and would be cooled there to about 55 F before being returned to thespaces to provide cooling. However, with the PCM present, the warm airwill pass over the material and be cooled by the PCMs that are at 68-70F. The PCM will liquefy as it absorbs energy from the air. By the timethe air reaches the air handling unit it will have been cooled to about70 F compared to the 80 F temperature it would have arrived at withoutPCM. On the one hand, the air has to be cooled from 80 to 55 F or 25 F,on the other the air only has to be cooled from 70 to 55 F or 15 F. Inarid climates this represents a forty percent reduction in peak coolingload. However, in most other climates moisture is also removed at theair handler so a thirty percent (30%) reduction in peak load ispossible.

The system of FIG. 7 reduces the rising cost of electricity/gas forcooling/heating a building. A derivative, but increasingly important,problem is environmental impact. Increasingly, architects and end usersare taking electricity consumption explicitly into account, e.g. bypenalizing inefficient products through the award (or non-award) ofLEEDS points. The tile of FIG. 7 minimizes electricity consumption is(a) directly economically attractive to an end user, (b) attractive to adeveloper (who might incur higher upfront costs but can offer reducedenergy consumption as a virtue to his lessors) and (c) attractive toarchitects/specifiers who are seeking energy efficiency.

The system performs automatic DR, reduces AC cost by 35% and shifts thedemand peak by automatically releasing cooling energy during the day andwarmth at night. Such systems provide a full range of options for bothpeaking and energy capacities across the electrical system and we passon the attendant energy savings to customers. Utilities and consumersbenefit through increased electric system reliability and reduced pricevolatility.

FIG. 8 shows an embodiment with two layers of PCM structures 210 and220. FIG. 9 shows an embodiment with cylindrical PCM structures 230.

FIGS. 10A-10C show alternative embodiments. In FIG. 10A, the structure240 containing the PCM is rectangular. In FIG. 10B, a honeycombstructure 250 provides strength and thermal conductance to maximizeenergy transfer between ambient air and the PCM material. In FIG. 10C,the structure 260 is cylindrical. Alternatively, the structure 260 canbe a layer of PCM balls glued or attached to the tile 200.

FIG. 11 shows one embodiment with multi-directional air flow. In thisembodiment, a tile or floor panel 300 has a PCM layer 310 with aplurality of ports 312 that crisscross each other from multiple sides ofthe tile/floor panel so that the air flow is not blocked, regardless ofthe position of the tile or floor panel 300 relative to the airflow.This embodiment allows orientation free installation of the tile orfloor unit. The ports can be fabricated by depositing a first layer ofPCM above a finished tile/floor panel, curing the first layer of PCM,then depositing a second layer whose air flow is at a 90 degree off setto conduct air flow from a different side of the tile/panel and thencuring the second PCM layer. This process can be used to fabricate asmany PCM layers as desired.

The process is applicable to several porous materials including cement,ceiling tiles and gypsum wallboards. In case of gypsum wallboards, theboard could be a standard board or a board with fiberglass (thefiberglass is added to increase internal bond strength). If an increaseof the board internal thermal conductivity is necessary, the board couldcontain metallic fibers. If an amount of PCM larger than what the boardcan retain is needed, the board could contain a wetting agent. Ifinflammability of the board does not meet standards for the application,a fire retardant could be added to the PCM or to the board duringmaking. The paper on the absorption face could be the one used at thepresent time or a more porous paper or a perforated paper or a thinnerpaper or another type of porous film to increase the rate of absorption.

As a general rule, during the absorption operation, the temperature ofthe board has to be above the melting temperature of the PCM but underthe maximum temperature that the board or PCM can reach without anydeterioration or degradation of properties. In the case of a paraffinabsorption into gypsum wallboards, the maximum temperature is about 95°C.; over this temperature there is a risk of deterioration of theinterface gypsum-paper. Laboratory tests have also shown that the rateof paraffin absorption into gypsum wallboards increases when the boardtemperature is increased. Another possibility is to increase thetemperature only on the absorption face to concentrate the PCM in thispart of the volume. This could be made by radiant heating, by a quickcooling of the other side or using a hot PCM on a colder board. Thetemperature of the PCM has to be above its melting point and in manycases its viscosity is reduced while heated; this improves the rate ofabsorption.

If not micro-encapsulated, the PCM must be compatible with the materialof the board. The PCM must not represent any risk for health and has tobe chemically and physically stable over a long period. The necessaryamount of PCM must be retainable by the board material and a wettingagent could be added, if necessary. A list of organic PCM with possibleadditives is given in U.S. Pat. No. 4,797,160 by Salyer. In an actualmanufacturing process as presently practiced, the PCM absorption couldbe performed immediately after the boards exit or are removed from thedrying oven (their temperature being at that moment about 90° C.)

When the PCM absorption operation is completed, the face of the board,through which the PCM has been absorbed, could remain as is or could becovered with a protective coating or material The surface could becovered with a paint or a varnish or a paper to prevent losses of PCM byevaporation and by capillarity with other materials in direct contactwith the board. In the case of ceiling tiles and gypsum wallboardsimpregnated using the back surface, covering of the surface by analuminum film could prevent heat loss or gain by radiation from insidethe wall or ceiling, could prevent losses of the PCM, could preventbacteriological deterioration of the PCM and could reduce theinflammability of the impregnated board.

In one embodiment shown in FIG. 12A, a ceiling tile or floor panel 1 isdisposed on a moving conveyor belt 2 with the surface to be impregnatedon top. The board 1 enters a spray chamber 3 inside of which a uniformamount of liquid PCM 4 strikes the surface. The rate of liquid sprayedis less than the rate of absorption into the board to avoid liquidaccumulation on the surface. The amount of PCM impregnated into theboard depends on the belt speed or on the spray chamber length. Forinstance, consider a spray chamber 15 m long and a spray rate of 1 L/m2.min; to absorb 1.25 L/m 2 into boards the belt speed has to be 0.2m/s. A roller 11 with a plurality of predetermined shapes 13 (or pattern13) is positioned at the output end, and the roller is positioned by acomputer to form continuous grooves or ridges or patterns on thetile/panel 2 in one embodiment. If the spray is used, a textureaggregate filler mixed with said PCM, the filler can be one of: perlite,glass microballoons, glass bubbles, phenolic microballoons, andmicrospheres.

Perlite is a well-known generic term for naturally occurring silicousrock, namely, sodium potassium aluminum silicate, typically of volcanicorigin. The distinguishing feature that sets perlite apart from othervolcanic glasses is that, when heated to a suitable point in itssoftening range, perlite expands from four to twenty times its originalvolume. This expansion is known to be due to the presence of two to sixpercent combined water in the crude perlite rock. When quickly heated toabove 1600° Fahrenheit (871° Centigrade), the crude rock pops in amanner similar to popcorn as the combined water vaporizes and createscountless tiny bubbles, which account for the amazing light weight andother well-known exceptional properties of expanded perlite. Thisexpansion process also creates perlite's white color, and the color ofexpanded perlite ranges from snowy white to grayish white. Becauseperlite is a form of natural glass, it is classified as chemically inertand has a pH of approximately 7.

A suitable and preferred aggregate for use in the coating of the presentinvention is hollow glass microspheres of expanded perlite sold underthe trademark DICAPERL and manufactured by Grefco, Inc., 3435 W. LomitaBoulevard, Torrance, Calif. 90509. The DICAPERL expanded perlite isamorphous mineral silicate (sodium potassium aluminum silicate ofvolcanic origin) containing a low percentage (less than 1%) ofcrystalline silica, and this aggregate has a variety of sphere sizesdenoted by product sizes DICAPERL HP-120, HP-220, HP-520, and HP-820.

DICAPERL expanded perlite is commonly used in the fiberglass industry asa lightweight filler for extending resin and for lightweight putties.Such fillers are relatively inert organic or inorganic materials thatare added to plastics resins or gel coats for special flowcharacteristics, to extend volume, and to lower the cost of a fiberglassarticle being produced. DICAPERL expanded perlite belongs to a group offillers called “lightweight fillers” that are able to reduce densitiesto those approaching wood. Such lightweight fillers are able to do thisbecause they contain an air void that displaces volume and lowers thebulk density. While there are various types of lightweight fillers, theyare all fragile and can be easily broken with high shear mixing. Oncethe particle has been fractured, the lower weight advantage is lost.There are several known lightweight fillers, namely, the groupconsisting of perlite, glass microballoons glass bubbles, phenolicmicroballoons, Q cel microspheres, and extendospheres.

In another embodiment, to provide for textured finish that enables highthermal interaction with air flow, the PCM can include large and/orheavy aggregate such as river sand or portland cement, as well asstucco-like finishes that can be shot through hopper guns or appliedusing a trowel or a paint roller. The texture can be varied by theweight and size of aggregate, the thickness of the medium holding theaggregate, and the manner of application (hopper gun, trowel, orroller). For example, in FIG. 12B the sprayers are replaced bysuccessive porous rolls 5 continuously fed with liquid PCM 6. Thetexture alone may be sufficient for thermal interaction with air flow,and the rolls 5 may additionally provide a series of predeterminedshapes 13 that form continuous grooves or ridges or patterns on thefinished tile or panel 2.

The flooding process shown in FIG. 12C is better adapted to a smallscale production. The board 1 is disposed at level and has its surfaceto be impregnated on top. A grid 7 is placed on the surface to createseparate small surfaces to flood with the desired amount of liquid PCM 8released by hopper gun nozzles or spouts 9. The PCM can include largeand/or heavy aggregate such as river sand or portland cement, as well asstucco-like finishes that can be shot through hopper guns or appliedusing a trowel or a paint roller. The result is a highly rugged texturethat interacts with conditioned air flow. Afterward, a template 15containing the desired shape may optionally be stamped on the board 1 toform grooves or ridges or patterns on the finished tile.

In another alternative, the surface to be impregnated with solid PCM orpartially melted PCM when the board is hot or on a cold board which isheated. If the rate of melting is lower than the rate of absorption, noliquid accumulation will occur on the surface.

FIG. 13A shows a field embodiment for adding the PCM materials in thefield. Referring to FIG. 13A, a sprayable textured coating 20, shownbeing sprayed onto a surface 21, comprises melted PCM 22 into which ismixed a texture aggregate filler 24, for example perlite as describedabove. It shall be understood that the scale of the coating 20 andsurface 21 is greatly exaggerated, for the sake of illustration, withrespect to the spray gun 26 and supply vessel 28. Surface 21 may be, forexample, ceiling tile, floor tile, or objects made of fiberglass, metal,masonry, high-density foam, painted wood and other materials used on theinterior and exterior of buildings.

Referring now to the drawings, there is shown self-contained portablepressure apparatus and hand spray gun assembly particularly suitable forspraying a texture coating material on floors, walls, ceilings, etc.which in FIG. 13B is shown in an operating position. The apparatus shownin general is comprised of a pressurized air tank or cylinder 611releasably mounted on a backpack carrier 612 together with a handleattachment 613 releasably fastened to the tank. A pressure control andcoupling line 614 is coupled between an outlet of the tank and an inletof a hand spray gun 615 having a feed hopper 616. The backpack tankcarrier 612 is positioned on the back of a user represented at 618 andsupports the pressurized air tank 611 while the spray gun 615 is held inone hand with the line 614 being sufficiently long to afford ease ofmovement of the spray gun. The pressurized tank 611 is a conventionalhigh pressure air cylinder or bottle normally filled with compressed airto a pressure of about 2,500 pounds per square inch, the tank having anon-off control valve 620 on top regulated by a knob 621 and also havinga tapered recess around an outlet 622 surrounded by an O-ring 623. Thepressurized tank 611 complies with OSHA safety standards.

The backpack tank carrier 612 comprised of a generally L-shaped supportframe adapted for supporting the tank having a flat base plate with anupturned retaining flange on one edge and an upright support plateextending up from an edge of the base at right angles thereto andopposite the retaining flange for providing a back side for supportingthe tank. A side gusset plate is secured at the side at each cornerbetween the base plate and upright support plate. An auxiliary plate issecured across the upright support plate providing a pair of sideextensions beyond the side edges of the upright support plate. A rigidshoulder strap is affixed at one end on a side extension of theauxiliary plate to be essentially flush with plate and extends up, outaway from and back down so as to be generally arcuate to fit over theshoulders of the user. In turn, a rigid shoulder strap is affixed to theother side extension of the auxiliary plate. A cushion member of arubber or rubberized material fits over the strap and a similar cushionmember on strap to engage the shoulders of the user for comfort. Theshoulder straps are constructed and arranged on the frame so that whendisposed on its side with the corner of the frame on a support surface,the shoulder straps dispose the tank at an angle of inclination with theupper end portion of the tank substantially above the support surfaceand the angle and weight distribution of the tank is such that there isno tendency to tip over toward the top so as to damage the tank valve620. In this way the tank valve 620 is protected against an accidentalsharp blow or the like.

For releasably securing the tank to the carrier frame there is shown anarcuate stationary arm 36 that is affixed at one end to an upper portionof the upright support plate 27 and is curved to extend partially aroundthe tank and an arcuate movable arm 37 that is pivotally attached to theupright support plate 27 by means of a hinge 38 so that it will extendpartially around the opposite side and co-operate with the stationaryarm 36 to secure the tank to the carrier. A releasable buckle-typefastener is secured at the free ends of the support arms. This fasteneris conventional and is in the form of a hook 41 on the movable arm 37and loop and lever member 42 on the stationary arm 36 so that when thelever is pivoted to one side it is closed and the arms are tightly heldagainst the tank and when pivoted to the other side the loop is movedout of the hook. The movable arm 37 is shown in an open position indashed lines at 37′ in FIG. 5 allowing the tank to be removed from thecarrier.

To provide for manually carrying the backpack carrier 612 and tank 611assembly to the point of use the handle attachment 613 is releasablymounted on an upper portion of the tank. This handle attachment 613 hasa C-clamp portion 648 in the form of relatively wide plate bent alongits length to conform to the circular transverse cross section of thetank in a C-clamp arrangement and further has a pair of opposed extendedportions 649 and 650 through which screw fasteners 651 extend so that itclamps firmly against the tank. Extension 650 is elongated andterminates in a rounded grip portion 652 covered by a cylindrical hollowcushion 653 and is also provided with a slot 654 allowing the user toinsert the fingers into the slot and grip the cushion and grip portion652. The handle attachment 613 is located on a center line above themidpoint between the top and bottom of the tank so that when the handleis gripped, there is a counter balancing effect whereby the lower partof the tank remains in a dependent lowermost position.

For further releasably securing the carrier frame to the user there isprovided a belt 645 that extends through a pair of slots in the supportplate to extend around the body of the user together with a buckle onthe free ends of the belt to fasten said free ends of the belt together.

The line pressure control and hose coupling 614 comprise a conventionalpressure regulator tank valve 661 adapted to be releasably coupled tothe valve 620 on the tank having an outlet coupled by a length offlexible hose 662 to the inlet of a pressure regulator 663 having apressure indicator 64 and control knob 65. A commercially availableregulator 663 is Wilkerson No. 2019-21. A length of flexible hose 666 iscoupled to the outlet of the pressure gauge to the inlet of an on-offair valve 667 which in turn coupled to the inlet of the spray gun 615.Conventional brass fittings are shown on the ends of the flexible hosesand these fittings are attached to the tank valve 661, pressureregulator gauge 662 and on-off valve 667 in sequence in the flow line.

The tank valve 661 is a conventional commercially available unit and hasa portion 671 that fits over the O-ring on the valve 620 and a threadedscrew that releasably locks the tank valve 61 in place on the top of thetank as shown in FIG. 1. The pressure regulator tank valve 661 reducesthe tank pressure from about 2,500 psi to 110 to 95 psi. In turn, thepressure gauge will control the pressure from 110 psi down to 0 psi togive a full range of pressure control for operating the spray gun orlike load. The on-off valve 667 permits the selective shutting off ofthe pressure to the spray gun entirely.

The spray gun shown is conventional Pattern Piston such as that sold byGoldblatt. The feed hopper 616 is releasably held on the gun by a hoseclamp 675 at its lower end. The feed hopper has a handle 676 and an openupper end into which the fluent coating material is poured. In the handcarrying of the apparatus, the spray gun 615 and line pressure controland coupling assembly is placed in the hopper. In one embodiment, aheater is provided to melt the PCM materials and a mixing blade is usedto mix the melted PCM materials with aggregates to provide tall texturesthat provide thermal interactions with the conditioned air flow.

The spray gun shown has an air pressure inlet, a spring biased controltrigger, a material cavity receiving material from the feed hopper 616by gravity flow, a rubber jacket with a hollow beveled head is movableagainst a rubber washer whereby as the trigger is pulled back,compressed air forces the material through an aperture in the rubberwasher. The gun also has a ring forming an outlet orifice alines withthe rubber washer that determines the pattern. These things will affectthe texture of the material being sprayed: the size of the orifice, theliquid state of the material and the air pressure.

FIG. 13C shows an exemplary PCM liquid applicator similar to a paintroller but for dispensing PCM onto building materials. The roller isgenerally designated 710 which includes a cylindrical roller 712 havingan exterior cylindrical surface 714 which is porous for the flow of aPCM liquid to be applied to a surface therethrough. The outer poroussurface 714 is mounted over a cylindrical core 716 which has a closure718 at one end and an end wall 720 at an opposite end which encloses apressure space 722 interiorly of the porous applicator wall 714 and theporous wall 716. The roller 712 is supported for rotation on supportmeans 723 which includes a handle portion 724 and a rotational supportportion 726. The handle portion 724 is connected through a tubular part728 to the rotational support portion 726 which connects through ajournal fitting 730 of the end closure 720 of the roller 712. In oneembodiment three separate supply passages for the paint 732, 734 and 736connect from a common PCM supply line 738 and pass through an outertubular covering 42 within the section 28 to the section 26 and throughto the fitting 30. These three separate supply conduits connectindividual supply conduits 32′, 34′ and 36′ inside the paint roller 12and they have discharge openings which discharge into a radial spacebetween the interior cylinder 16 and the roller transfer surface 14.This annular space 22 is thus maintained under pressure supplied from apump 40 which is mounted on a paint can cover cap 42. The pump 40 takessuction through a suction line 44 which is dipped into an ordinary paintcan 46 and which is closed by the cover fitting 42. The paint isdischarge by the pump 40 through the discharge conduit line 38 where itbranches to the conduits 32, 34 and 36 and flows through the conduits32′, 34′ and 36′ to the various sections of the pressure space 22located along the length of the interior of the applicator surface 14.Paint may be returned by the build up of pressure if necessary through areturn opening 48 which connects through a radial channel 50 of thefitting 30 and connects through a return line 52 for return to the pump.The amount of pressure which is maintained between the interior hollowcylinder 16 and the porous surface 14 may be varied by controlling therate of return of the paint through the return line or by controllingthe speed of operation of the pump 40.

The pump 40 is advantageously driven by a variable speed electric motorwhich is supplied with electricity through a battery (not shown) orthrough a connecting port 754. The electrical wires are transmittedthrough a conduit 756 up through the handle 724 and they pass throughthe handle and the section 728 to a drive motor 758 for driving theroller at a controlled rotational speed. While the motor is an electricmotor having an output shaft which drives through gears it mayadvantageously comprise a fluid motor which is operated by the fluidpressure generated by the pump motor driving the paint to the roller.The gear is carried on the inner cylinder and rotates it along with theouter applicator surface at a rate which is varied in accordance withthe thickness of paint to be deposited during each revolution. Thehandle 724 advantageously includes an on and off button 766 for theroller drive motor and an on and off button 768 for the pump motor 740.The control button 766 may also include a speed variation for the drivemotor if desired. In addition the handle contains a control button 770for distributing the paint flow from the discharge 738 of the pump 740to each of the three separate lines. For this purpose the control 770may be positioned in the center position at which point it has a portionwhich deflects a control valve pin to open the center conduit or it maybe positioned to either the left or to the right of the position toseparately open only the control lines by depressing valves. In additionit may be moved backwardly in an elongated slot defined in the handle todepress all three valves at once to permit flow through each one ofthem.

In one embodiment the handle 724 is provided with an end portion forminga PCM reservoir. The reservoir is filled by removing a cap and pouringaggregated PCM liquids into the reservoir when it is inverted and thensecuring the cap back in place by threading it onto a bottom handleportion. The handle contains a pump and drive motor which includes apump suction which extends into the bottom of the reservoir into thelower portion of the cap. In this embodiment the pump may be driven at acontrolled speed to discharge the paint through a discharge conduit at acontrolled rate for effecting the best application onto the paintreceiving surfaces. Some paint may be returned through a return lineback to the reservoir and this line may advantageously have a controlvalve for regulating the amount of paint which is returned.

As noted in Application 20100087115, phase change materials can beencapsulated in a number of materials to contain the PCM and prevent itfrom leaking out when in a liquid phase. In general, a PCM can be anysubstance (or any mixture of substances) that has the capability ofabsorbing or releasing thermal energy by means of a phase change withina temperature stabilizing range. The temperature stabilizing range caninclude a particular transition temperature or a particular range oftransition temperatures. A PCM is typically capable of maintaining atemperature condition during a time when the PCM is absorbing orreleasing heat, typically as the PCM undergoes a transition between twostates (e.g., liquid and solid states, liquid and gaseous states, solidand gaseous states, or two solid states). Thermal energy may be storedor removed from the PCM, and can effectively be recharged by a source ofheat or cold.

PCMs that can be used include various organic and inorganic substances.Organic PCMs may be preferred for the embodiments disclosed herein.Examples of phase change materials include hydrocarbons (e.g.,straight-chain alkanes or paraffinic hydrocarbons, branched-chainalkanes, unsaturated hydrocarbons, halogenated hydrocarbons, andalicyclic hydrocarbons), hydrated salts (e.g., calcium chloridehexahydrate, calcium bromide hexahydrate, magnesium nitrate hexahydrate,lithium nitrate trihydrate, potassium fluoride tetrahydrate, ammoniumalum, magnesium chloride hexahydrate, sodium carbonate decahydrate,disodium phosphate dodecahydrate, sodium sulfate decahydrate, and sodiumacetate trihydrate), waxes, oils, water, fatty acids, fatty acid esters,dibasic acids, dibasic esters, 1-halides, primary alcohols, secondaryalcohols, tertiary alcohols, aromatic compounds, clathrates,semi-clathrates, gas clathrates, anhydrides (e.g., stearic anhydride),ethylene carbonate, methyl esters, polyhydric alcohols (e.g.,2,2-dimethyl-1,3-propanediol, 2-hydroxymethyl-2-methyl-1,3-propanediol,ethylene glycol, polyethylene glycol, pentaerythritol,dipentaerythritol, pentaglycerine, tetramethylol ethane, neopentylglycol, tetramethylol propane, 2-amino-2-methyl-1,3-propanediol,monoaminopentaerythritol, diaminopentaerythritol, andtris(hydroxymethyl)acetic acid), sugar alcohols (erythritol, D-mannitol,galactitol, xylitol, D-sorbitol), polymers (e.g., polyethylene,polyethylene glycol, polyethylene oxide, polypropylene, polypropyleneglycol, polytetramethylene glycol, polypropylene malonate, polyneopentylglycol sebacate, polypentane glutarate, polyvinyl myristate, polyvinylstearate, polyvinyl laurate, polyhexadecyl methacrylate, polyoctadecylmethacrylate, polyesters produced by polycondensation of glycols (ortheir derivatives) with diacids (or their derivatives), and copolymers,such as polyacrylate or poly(meth)acrylate with alkyl hydrocarbon sidechain or with polyethylene glycol side chain and copolymers includingpolyethylene, polyethylene glycol, polyethylene oxide, polypropylene,polypropylene glycol, or polytetramethylene glycol), metals, andmixtures thereof.

The selection of a PCM is typically dependent upon the transitiontemperature that is desired for a particular application that is goingto include the PCM. The transition temperature is the temperature orrange of temperatures at which the PCM experiences a phase change fromsolid to liquid or liquid to solid. For example, a PCM having atransition temperature near room temperature or normal body temperaturecan be desirable for clothing applications. A phase change materialaccording to some embodiments of the invention can have a transitiontemperature in the range of about −5° C. to about 125° C. In oneembodiment, the transition temperature is about 6° C. to about 37° C. Inanother embodiment, the transition temperature is about 15° C. to about30° C. In another embodiment, the PCM has a transition temperature ofabout 30° C. to about 45° C.

Paraffinic PCMs may be a paraffinic hydrocarbons, that is, hydrocarbonsrepresented by the formula CnHn+2, where n can range from about 10 toabout 44 carbon atoms. PCMs useful in the invention include paraffinichydrocarbons having 13 to 28 carbon atoms. For example, the meltingpoint of a homologous series of paraffin hydrocarbons is directlyrelated to the number of carbon atoms as shown in the following table:

Compound Name # Carbon Atoms Melting Point (° C.) n-Octacosane 28 61.4n-Heptacosane 27 59.0 n-Hexacosane 26 56.4 n-Pentacosane 25 53.7n-Tetracosane 24 50.9 n-Tricosane 23 47.6 n-Docosane 22 44.4n-Heneicosane 21 40.5 n-Eicosane 20 36.8 n-Nonadecane 19 32.1n-Octadecane 18 28.2 n-Heptadecane 17 22.0 n-Hexadecane 16 18.2n-Pentadecane 15 10.0 n-Tetradecane 14 5.9 n-Tridecane 13 −5.5

Methyl ester PCMs may be any methyl ester that has the capability ofabsorbing or releasing thermal energy to reduce or eliminate heat flowwithin a temperature stabilizing range. In one embodiment, the methylester may be methyl palmitate. Examples of other methyl esters includemethyl formate,methyl esters of fatty acids such as methyl caprylate,methyl caprate, methyl laurate, methyl myristate, methyl palmitate,methyl stearate, methyl arachidate, methyl behenate, methyl lignocerateand fatty acids such as caproic acid, caprylic acid, lauric acid,myristic acid, palmitic acid, stearic acid, arachidic acid, behenicacid, lignoceric acid and cerotic acid; and fatty acid alcohols such ascapryl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearylalcohol, arachidyl alcohol, behenyl alcohol, lignoceryl alcohol, cerylalcohol, montanyl alcohol, myricyl alcohol, and geddyl alcohol.

Substantially any PCM (commonly a hydrophobic PCMs) which can bedispersed in water and microencapsulated by the technology referencedherein and may be useful in the present microencapsulated PCM.Alternately, two or more different PCMs can be used to addressparticular temperature ranges and such materials can be mixed. PCMs arecommercially available from PCM Energy P. Ltd, Mumbai, India, EntropySolutions Inc., Minneapolis, Minn., and Renewable Alternatives,Columbia, Mo.

Encapsulating a PCM that has a boiling point of about 230° C. to about420° C., preferably about 280° C. to about 400° C., and more preferablyabout 300° C. to about 390° C. provides enhanced flame resistance. ThePCM may be a synthetic beeswax, a non-halogenated PCM, or any currentlyexisting or later developed PCM that has a boiling point within thesetemperature ranges. In one embodiment, the PCM is a synthetic beeswax (aderivative mixture of fatty acid esters) having a melting point of 28°C. and a boiling point greater than 300° C. In another embodiment, themicrocapsule additionally has a flame retardant applied to themicrocapsule wall as discussed in more detail below.

Any of a variety of processes known in the art may be used tomicroencapsulate PCMs in accordance with the present invention.Microcapsule production may be achieved by physical methods such asspray drying or by centrifugal and fluidized beds.

The microencapsulated material may be provided using any suitablecapsule chemistry. Chemical techniques may be used, such as dispersingdroplets of molten PCM in an aqueous solution and to form walls aroundthe droplets using simple or complex coacervation, interfacialpolymerization and in situ polymerization all of which are well known inthe art. For example, methods are well known in the art to form gelatincapsules by coacervation, polyurethane or polyurea capsules byinterfacial polymerization, and urea-formaldehyde,urea-resorcinol-formaldehyde, and melamine formaldehyde capsules by insitu polymerization. U.S. Pat. No. 6,619,049, herein incorporated byreference, discloses a method for microencapsulating a PCM in a melamineformaldehyde resin.

The ceiling material may comprise a polyacrylate, as described in, forinstance, U.S. Pat. No. 4,552,811. Gelatin or gelatin-containingmicrocapsule materials are well known. The teachings of the phaseseparation processes, or coacervation processes, are described in U.S.Pat. Nos. 2,800,457 and 2,800,458 and gel-coated capsules, aspurportedly described in U.S. Pat. No. 6,099,894 further may be employedin connection with the invention.

Interfacial polymerization is a process wherein a microcapsule wall of apolyamide, an epoxy resin, a polyurethane, a polyurea or the like isformed at an interface between two phases. U.S. Pat. No. 4,622,267discloses an interfacial polymerization technique for preparation ofmicrocapsules. The core material is initially dissolved in a solvent andan aliphatic diisocyanate soluble in the solvent mixture is added.Subsequently, a nonsolvent for the aliphatic diisocyanate is added untilthe turbidity point is just barely reached. This organic phase is thenemulsified in an aqueous solution, and a reactive amine is added to theaqueous phase. The amine diffuses to the interface, where it reacts withthe diisocyanate to form polymeric polyurethane shells. A similartechnique, used to encapsulate salts which are sparingly soluble inwater in polyurethane shells, is disclosed in U.S. Pat. No. 4,547,429.

U.S. Pat. No. 3,516,941 teaches polymerization reactions in which thematerial to be encapsulated, or core material, is dissolved in anorganic, hydrophobic oil phase which is dispersed in an aqueous phase.The aqueous phase has dissolved materials forming aminoplast resin whichupon polymerization form the wall of the microcapsule. A dispersion offine oil droplets is prepared using high shear agitation. Addition of anacid catalyst initiates the polycondensation forming the aminoplastresin within the aqueous phase, resulting in the formation of anaminoplast polymer, which is insoluble in both phases. As thepolymerization advances, the aminoplast polymer separates from theaqueous phase and deposits on the surface of the dispersed droplets ofthe oil phase to form a capsule wall at the interface of the two phases,thus encapsulating the core material. This process produces themicrocapsules. Polymerizations that involve amines and aldehydes areknown as aminoplast encapsulations.

Urea-formaldehyde (UF), urea-resorcinol-formaldehyde (URF),urea-melamine-formaldehyde (UMF), and melamine-formaldehyde (MF) capsuleformations proceed in a like manner. In interfacial polymerization, thematerials to form the capsule wall are in separate phases, one in anaqueous phase and the other in a fill phase. Polymerization occurs atthe phase boundary. Thus, a polymeric capsule shell wall forms at theinterface of the two phases thereby encapsulating the core material.Wall formation of polyester, polyamide, and polyurea capsules proceedsvia interfacial polymerization.

Processes of microencapsulation that involve the polymerization of ureaand formaldehyde, monomeric or low molecular weight polymers ofdimethylol urea or methylated dimethylol urea, melamine andformaldehyde, monomeric or low molecular weight polymers of methylolmelamine or methylated methylol melamine are taught in U.S. Pat. No.4,552,811. These materials are dispersed in an aqueous vehicle and thereaction is conducted in the presence of acrylic acid-alkyl acrylatecopolymers. Preferably, the wall forming material is free of carboxylicacid anhydride or limited so as not to exceed 0.5 weight percent of thebuilding material.

A method of encapsulating by in situ polymerization, including areaction between melamine and formaldehyde or polycondensation ofmonomeric or low molecular weight polymers of methylol melamine oretherified methylol melamine in an aqueous vehicle conducted in thepresence of negatively-charged, carboxyl-substituted linear aliphatichydrocarbon polyelectrolyte material dissolved in the vehicle isdisclosed in U.S. Pat. No. 4,100,103.

In one embodiment, the building material for encapsulating the PCMcontains a melamine-formaldehyde resin. In an alternate embodiment, themicrocapsule may be a dual walled capsule. Dual wall capsules, such asfirst wall-second wall structures of an acrylic polymer and anurea-resorcinal-gluteraldehyde (URG), an acrylic polymer and anurea-resorcinal-formaldehyde (URF), a melamine-formaldehyde and a URF, amelamine-formaldehyde and a URG, or a URF and a melamine-formaldehyde,respectively, as disclosed in U.S. Published Patent Application2006/0063001, herein incorporated by reference.

The microcapsules will typically have a relatively high payload of PCMof about 60% to 85%. In one embodiment, the phase change material ispresent at about 70% to 80% by weight. The PCM may be one or acombination of the PCMs described above.

The size of the microcapsules typically range from about 0.01 to 100microns and more typically from about 2 to 50 microns. The capsule sizeselected will depend on the application in which the microencapsulatedPCM is used. For example, they may be used as the thermal transfermedium in a heat transfer fluid for use in lasers, supercomputers andother applications requiring high thermal transfer efficiencies. Theyalso may be coated on fibers or incorporated into fibers to prepareinsulative fabrics. They may be added to plastics or resins such aspolypropylene and acrylics and spun into fibers or extruded intofilaments, beads or pellets useful in thermal transfer applications suchas insulative apparel such as clothes, shoes, boots, etc., buildinginsulation for use in ceilings, floors, etc. For use in heat transferfluids, the capsule size may range from about 1 to 100 microns and moretypically from about 2 to 40 microns. For use in fibers, yarns, ortextile the capsule size may be about 1 to 15 microns or about 2 to 10microns. For other applications, the capsule size range is about 0.5microns to about 10 microns.

These microencapsulated PCM may be made of different tile thicknesses.Typically the tile material should be thick enough to contain the PCMwhile in its liquid phase. The thickness may be about 0.1 to about 0.9microns. In one embodiment, the tile may be about 0.2 to about 0.6microns thick with a nominal (mean) thickness of about 0.4 microns. Thecapsule walls should be sufficiently thick to avoid rupture whenprocessed into other materials or products, such as those discussedabove.

Those skilled in the art will appreciate that the capsule size and wallthickness may be varied by many known methods, for instance, adjustingthe amount of mixing energy applied to the materials immediately beforewall formation commences. Capsule wall thickness is also dependent uponmany variables, including the speed of the mixing unit used in theencapsulation process.

Other microencapsulation processes known in the art or otherwise foundto be suitable for use with the invention may be employed. In oneembodiment, a plurality of microencapsulated PCMs having the same ordifferent encapsulation may be contained in “macrocapsules” as disclosedin U.S. Pat. No. 6,703,127 and No. 5,415,222, herein incorporated byreference in their entirety. Macrocapsules may provide a thermal energystorage composition that more efficiently absorbs or releases thermalenergy during a heating or a cooling process than individualmicroencapsulated PCMs.

Various flame retardants may be used to enhance flame resistance of anencapsulated phase change material. In one embodiment, the flameretardant may contain one or more of boric acid, borates, ammoniumpolyphosphates, sodium carbonate, sodium silicate, aluminum hydroxide,magnesium hydroxide, antimony trioxide, various hydrates,tetrakis(hydroxymethyl)phosphonium salts, halocarbons, includingchlorendic acid derivates, halogenated phosphorus compounds includingtri-o-cresyl phosphate, tris(2,3-dibromopropyl)phosphate (TRIS),bis(2,3-dibromopropyl)phosphate, tris(1-aziridinyl)-phosphine oxide(TEPA), and others.

The flame retardant may be applied to the wall material as a solution,dispersion, a suspension, or a colloid that forms a coating on the wallmaterial to provide flame resistant characteristics to themicroencapsulated PCM. The flame retardant may be present in an amountto make about a 2% to about a 50% flame retardant solution, dispersion,suspension, or colloid. In another embodiment, the flame retardant maybe present in an amount to make about a 5% to about a 30% flameretardant solution, dispersion, suspension, or colloid. Any solvent maybe used dissolve, mix, or suspend the flame retardant withoutdecomposing or reacting with the flame retardant, the wall material, orany other solvents present. The solvent may be water, an aliphatic oraromatic solvent, and/or an alcohol. The application of the flameretardant as a solution, dispersion, suspension, or colloid (the flameretardant medium) is advantageous because it provides a relativelysimple manufacturing process as seen in the Examples below and describedin more detail in the Method section below.

A method for making a microencapsulated phase change material havingflame resistance may include providing an encapsulated phase changematerial and applying a composition containing a flame retardant to theencapsulated phase change material. The flame retardant composition maycontain any of the flame retardants described above or a combinationthereof and may be present in a solution, dispersion, suspension, orcolloid in the concentrations given above.

The flame retardant composition may be applied by spraying, pan coating,or by using a fluidized bed, industrial blender, or other various typesof mixers and/or blenders. In another embodiment, the encapsulated PCMsmay be suspended in a composition containing the flame retardant toallow a coating to form on the outer surface of the microcapsule wall.The composition may be a solution, dispersion, suspension, or colloid,as described above. The encapsulated PCMs way be added to thecomposition as a powder, wet cake, or as a slurry. A slurry may beadvantageous in mixing more quickly with the composition.

The flame retardant is applied in an amount of about 5% to about 30%flame retardant by weight of the coated microcapsule.

To vary the percent by weight of the flame retardant coating on themicroencapsulated PCMS the amount of time the microencapsulated PCMsremains in or is coated with the flame retardant medium may be altered.Theoretically, there is likely an amount of time that even if exceededwill not deposit more flame retardant on the microcapsules as anequilibrium state may be achieved between the flame retardant in theflame retardant medium and the amount of flame retardant deposited onthe microcapsules. Alternately, the amount or concentration of flameretardant in the flame retardant medium may also affect the amount offlame retardant deposited as well as the time it takes to deposit thedesired amount of flame retardant. One skilled in the art will alsorecognize that other factors may affect the time and amount of flameretardant deposited such as temperature, pressure, agitation of themedium, etc.

After the flame retardant coating is applied the coated microcapsulesare removed from the composition and are dried. The removal of thecoated encapsulated PCMs from the solution, dispersion, suspension, orcolloid may be by any conventional process, such as filtering orcentrifuging. The coated encapsulated PCMs may be dried thereafter usingany convention process, such as air drying, oven drying, spray drying,or fluid bed drying. The coated microcapsules may be dried to about a 5%moisture content or less. The microcapsules may have a moisture contentof about 1% to about 2%. Alternately, rather than drying the coatedencapsulated PCMS, the microcapsules may be contained as a wet cake. Thewet cake may have a moisture content of about 30%.

The coated encapsulated PCMs may have a variety of uses because manyindustries may be able to take advantage of the coated capsules flameresistance. The flame resistant encapsulated PCMs may be incorporatedinto a number of articles such as textile materials, building materials,packaging materials, and electronic devices. Textile materials may havethe coated encapsulated PCMs incorporated into the fiber and/or fabricsthey are made of The textile material may be used to make clothingitems, window treatments, and medical wraps to provide flame resistanceand the thermal characteristics of the PCM. Building materials mayinclude the flame resistant encapsulated PCMs on or in them, such asinsulation, lumber, roofing materials, and floor and ceiling tiles.Packaging materials may include food serving trays, bubble wrap,packaging peanuts, labels, cardboard, paper, and insulated containers.Electronic devices may include the coated encapsulated PCMs to removeheat from electrical components that may be damaged by heat, such ascomputers, televisions, or any other machine with electronic components.The coated encapsulated PCMs may also be incorporated into a binder toprovide a coating useful in many applications, such as paints, sprays,etc. that may even be useful in applying the coated encapsulated PCMs tothe items described above.

The present invention, in various embodiments, includes components,methods, processes, systems and/or apparatus substantially as depictedand described herein, including various embodiments, subcombinations,and subsets thereof. Those of skill in the art will understand how tomake and use the present invention after understanding the presentdisclosure. The present invention, in various embodiments, includesproviding devices and processes in the absence of items not depictedand/or described herein or in various embodiments hereof, including inthe absence of such items as may have been used in previous devices orprocesses, e.g., for improving performance, achieving ease and\orreducing cost of implementation.

The foregoing discussion of the invention has been presented forpurposes of illustration and description. The foregoing is not intendedto limit the invention to the form or forms disclosed herein. In theforegoing Detailed Description for example, various features of theinvention are grouped together in one or more embodiments for thepurpose of streamlining the disclosure. This method of disclosure is notto be interpreted as reflecting an intention that the claimed inventionrequires more features than are expressly recited in each claim. Rather,as the following claims reflect, inventive aspects lie in less than allfeatures of a single foregoing disclosed embodiment. Thus, the followingclaims are hereby incorporated into this Detailed Description, with eachclaim standing on its own as a separate preferred embodiment of theinvention.

Moreover, though the description of the invention has includeddescription of one or more embodiments and certain variations andmodifications, other variations and modifications are within the scopeof the invention, e.g., as may be within the skill and knowledge ofthose in the art, after understanding the present disclosure. It isintended to obtain rights which include alternative embodiments to theextent permitted, including alternate, interchangeable and/or equivalentstructures, functions, ranges or steps to those claimed, whether or notsuch alternate, interchangeable and/or equivalent structures, functions,ranges or steps are disclosed herein, and without intending to publiclydedicate any patentable subject matter.

1. An appliance, comprising: a memory storage location storing a flagindicative of a predicted demand-response (DR) period; a non-electricalenergy source to provide temporary energy during the DR period; and acontroller reading the flag to autonomously place the appliance in anenergy shedding mode during the predicted DR period.
 2. The appliance ofclaim 1, wherein the predicted DR period occurs when the specified dutycycle comprises 60 hertz and the current AC power duty cycle comprisesabout 59.5 hertz or less.
 3. The appliance of claim 1, comprising: awide area network coupled to the sensor; and a server coupled to thewide area network, wherein for each appliance the server stores alocation, a user preference, and appliance properties, and wherein theserver receives periodic operating state update and time stamp from eachappliance.
 4. The appliance of claim 3, wherein the controller indicatesthe location of the appliance using an internet protocol (IP) address.5. The appliance of claim 3, wherein the controller indicates thelocation of the appliance using an address selected from one of:(consisting of) a user entered address, an address stored in anotherappliance, and an address determined by a positioning system.
 6. Theappliance of claim 1, wherein the server determines a first group ofappliances in an uninterruptible phase and sends a DR overrideinstruction to the controller(s) in the first group.
 7. The appliance ofclaim 1, wherein the server modulates operations of appliances to avoidstressing the electrical grid.
 8. The appliance of claim 1, wherein theappliance comprises a sensor compares the current AC duty cycle againstthe specified AC duty cycle and sets the flag indicative of a predicteddemand-response (DR) period.
 9. The appliance of claim 1, comprising apower sensor external to the appliance, wherein the power sensorcompares the current AC duty cycle against the specified AC duty cycleand sets the flag indicative of a predicted demand-response (DR) period.10. The appliance of claim 1, wherein the appliance is a refrigerator,further comprising: an ice energy storage chamber providing apredetermined cold energy for a refrigerated volume for the predicted DRperiod; and a fan to circulate cold air from the ice energy storagechamber inside the refrigerated volume during the predicted DR period.11. The appliance of claim 1, wherein the appliance is a refrigerator,further comprising a phase change material coupled to the refrigeratedvolume to maintain the refrigerated volume at a predeterminedtemperature during the predicted DR period.
 12. The appliance of claim1, wherein the appliance is a refrigerator and wherein the controllermodulates compressor operation to reduce power consumption during thepredicted DR period.
 13. The appliance of claim 1, wherein the applianceis a refrigerator, and wherein the controller precharges therefrigerator prior to the predicted DR period.
 14. The appliance ofclaim 13, wherein the appliance is a refrigerator, and wherein thecontroller precharges the refrigerator based on weather or warning froman authority.
 15. The appliance of claim 1, wherein the appliance is arefrigerator, comprising an ice storage to store coolth during night andused for air-conditioning during day.
 16. The appliance of claim 1,wherein the appliance is a water heater, comprising: a back-up heatedenergy storage chamber to store a reserve heated water to maintained apredetermined temperature output for the water heater during thepredicted DR period; and a valve to mix the reserve heated water withthe water in the main water heater tank during the predicted DR period.17. The appliance of claim 15, wherein the appliance is a water heater,further comprising a phase change material coupled to the water volumeto maintain the water at a predetermined temperature during thepredicted DR period.
 18. The appliance of claim 15, wherein theappliance is a water heater and wherein the controller modulates heateroperation to reduce power consumption during the predicted DR period.19. The appliance of claim 15, wherein the appliance is a water heater,and wherein the controller precharges the water heater prior to thepredicted DR period.
 20. The appliance of claim 18, wherein theappliance is a water heater, and wherein the controller precharges thewater heater based on weather or warning from an authority. 21-28.(canceled)